两个向量的点积
import numpy as np
a1 = np.array([1, 2, 3, 4, 5])
a2 = np.array([2, 3, 4, 5, 6])
a3 = np.dot(a1, a2)
print(a3) # 70,对应位置的值相乘再相加
向量与矩阵的点积
import numpy as np
# 矩阵与向量的点积
matrix = np.array([
[1, 2, 3, 4, 5],
[6, 4, 3, 2, 1]
])
vetor = np.array([3, 6, 5, 2, 1])
result = np.dot(matrix, vetor)
print(result)
"""
[43 62]
"""
矩阵与矩阵的点积
import numpy as np
# 矩阵与矩阵的点积
matrix1 = np.array([
[1, 2, 3, 4, 5],
[6, 4, 3, 2, 1]
])
matrix2 = np.array([
[8, 2, 3, 4, 5],
[6, 4, 3, 2, 1],
[6, 4, 3, 2, 1],
[6, 4, 3, 2, 1],
[6, 4, 3, 2, 1]
])
result = np.dot(matrix1, matrix2) # matrix的行与 atrix的列之间的点积
print(result)
"""
[[ 92 58 45 32 19]
[108 52 48 44 40]]
"""